One of the most powerful features of ColdFusion is the ability to extend the core capabilities of the platform through custom tags. Custom tags allow you to encapsulate code in a neat wrapper that can then be invoked from within any CFML template. Those familiar with other programming languages can think of custom tags as similar to subroutines or procedures.
There are two varieties of custom tags: custom CFML tags (referred to as custom tags) and CFX tags. Because developing CFX tags requires C++ or Java experience, this chapter focuses on the development and use of custom tags, since they are written in CFML. A brief section at the end of the chapter discusses installing and calling CFX tags.